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91.
Graeme W. Carlile Robert A. Keyzers Katrina A. Teske Renaud Robert David E. Williams Roger G. Linington Christopher A. Gray Ryan M. Centko Luping Yan Suzana M. Anjos Heidi M. Sampson Donglei Zhang Jie Liao John W. Hanrahan Raymond J. Andersen David Y. Thomas 《Chemistry & biology》2012,19(10):1288-1299
92.
This paper contains a theoretical analysis of orientation and alignment created in direct, collision-induced transitions among atomic states with arbitrary angular momentum. Using the natural coordinate frame, general propensity rules are derived in the velocity region of maximum transition probability and their range of validity is investigated. The predictions are tested and illustrated by nine-state calculations for Li(n=2, 3) transitions in Li-He collisions. 相似文献
93.
P state orientation and alignment created in direct, collision-inducedS ?P transitions of a quasi-one-electron atom are analyzed in the natural coordinate frame. In the velocity region of maximum transition probability, propensity rules for the orientation are derived, and their range of validity in impact parameter and velocity is discussed. The predictions are tested and illustrated by three-state calculations for Na(3s ? 3p) transitions in Na — He collisions. 相似文献
94.
Andre Silva Pimentel Geoffrey S. Tyndall John J. Orlando Michale D. Hurley Timothy J. Wallington Mads P. Sulbaek Andersen Paul Marshall Theodore S. Dibble 《国际化学动力学杂志》2010,42(8):479-498
Formates are produced in the atmosphere as a result of the oxidation of a number of species, notably dialkyl ethers and vinyl ethers. This work describes experiments to define the oxidation mechanisms of isopropyl formate, HC(O)OCH(CH3)2, and tert‐butyl formate, HC(O)OC(CH3)3. Product distributions are reported from both Cl‐ and OH‐initiated oxidation, and reaction mechanisms are proposed to account for the observed products. The proposed mechanisms include examples of the α‐ester rearrangement reaction, novel isomerization pathways, and chemically activated intermediates. The atmospheric oxidation of isopropyl formate by OH radicals gives the following products (molar yields): acetic formic anhydride (43%), acetone (43%), and HCOOH (15–20%). The OH radical initiated oxidation of tert‐butyl formate gives acetone, formaldehyde, and CO2 as major products. IR absorption cross sections were derived for two acylperoxy nitrates derived from the title compounds. Rate coefficients are derived for the kinetics of the reactions of isopropyl formate with OH (2.4 ± 0.6) × 10?12, and with Cl (1.75 ± 0.35) × 10?11, and for tert‐butyl formate with Cl (1.45 ± 0.30) × 10?11 cm3 molecule?1 s?1. Simple group additivity rules fail to explain the observed distribution of sites of H‐atom abstraction for simple formates. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 479–498, 2010 相似文献
95.
S. P. L. Sörensen A. C. Andersen Kutscher und Steudel 《Fresenius' Journal of Analytical Chemistry》1906,45(5-6):354-355
Ohne Zusammenfassung 相似文献
96.
In vitro exposure of human lymphocyte cultures to spindle inhibitors reduce the average chromosome length1,2. In this report chromosome length measurements were used for indirect but quantitative evaluation of the effects of inorganic and organic lead compounds on spindle function. The data indicate that organic compounds are much more powerful spindle inhibitors than inorganic lead compounds, almost as potent as colchicine. Occupational exposure to organic lead compounds may result in partial spindle inhibition, leading to a high probability of nondisjunction. 相似文献
97.
98.
J.O. Andersen 《The European Physical Journal C - Particles and Fields》1999,11(3):563-570
Dimensional reduction and effective field theory methods are applied to the Two Higgs Doublet Model at finite temperature.
A sequence of two effective three-dimensional field theories which are valid on successively longer distance scales is constructed.
The resulting Lagrangian can be used to study different aspects of the phase transition in this model as well as the sphaleron
rate immediately after the phase transition.
Received: 14 March 1999 / Published online: 22 October 1999 相似文献
99.
A. L. Nielsen M. B. O. Andersen T. V. Bugge C. F. Nielsen T. B. Nielsen R. Wimmer D. Yu K. L. Larsen 《Journal of polymer science. Part A, Polymer chemistry》2009,47(23):6619-6629
In this article, we present the synthesis and characterization of water‐soluble polymers with hydrophobic moieties. The polymers were synthesized in aqueous solutions utilizing β‐cyclodextrins as solubility enhancers to bring the hydrophobic monomers into solution. Polymers were made with different spacing between polymer backbone and phenyl moiety by using styrene, allylbenzene, and 4‐phenyl‐1‐butene as hydrophobic moieties, respectively. The effect of the presence of CDs during synthesis as well as this difference in spacing was investigated by rebinding free β‐CDs to the polymers. The interactions between polymers and CDs were studied by ITC and this revealed some differences between the polymers. Polymers made in the presence of CDs showed a markedly stronger binding to free CDs. The same was observed with polymers with a longer spacing between backbone and phenyl moiety. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6619–6629, 2009 相似文献
100.